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PVC is a versatile polymer used in a diversity of applications, function of its own, as well as its blending component’s properties. Since the early 1930s, when commercial production of PVC started, it became a universal polymer due to its high performance and low cost, combined with the broad range of items that can be obtained by multiple processing techniques and variable parameters. For enhanced performances, PVC can be mixed with (bio)plasticizers, thermoplastics, rubbers, polysaccharides, minerals, natural fillers or other types of additives in order to improve PVC blends compatibility. PVC is found in various applications, such as building, packaging, automotive, military and aeronautic industries, medicine, ships construction, life rafts, garden hoses, swimming rings, footballs, toys, different cards and so on. PVC is also used in the preparation of membranes (e.g., for water treatment), owing to its good mechanical strength, abrasion resistance, chemical stabilization, thermal properties, low cost and corrosion resistance. Different factors affect the properties of PVC composites, such as processing techniques and parameters, the origin of the filler, its particle size and its aspect ratio, as well as its concentration and the homogeneity of its distribution in the polymer matrix. PVC bionanocomposites can be also produced by using nanoelements resulted from different renewable resources, e.g., cellulose, starch, chitin, inducing also PVC’s biodegradability.

The epoxy composites were synthesized from epoxy resin ED-20, polyethylene polyamine as curing agent and copper nanopowder and boric acid as fillers. The copper nanopowder was produced by electrical explosion of wires. The thermal properties of the epoxy composites at the heating in the atmosphere of air and argon from ambient temperature to 900 °C were characterized using thermogravimetric analysis and differential scanning calorimetry. The results showed that copper nanopowders catalyzed thermal oxidative degradation of the epoxy composites. The effect of the addition of boric acid in the epoxy polymer filled with copper nanopowder on the thermal stability of the composite at the heating in air was studied. It was found that the boric acid addition inhibited the degradation process. The limiting oxygen index was calculated in accordance with Van Krevelen and Hoftyzer equation.

The particles of natural zeolite in combination with boric acid were incorporated into the epoxy resin ED-20 in order to improve the thermal stability of epoxy polymer. Epoxy resin was cured using polyethylenepolyamine. Characterization of the epoxy composites was carried out by using Fourier transform infrared spectrometry, thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) under flow of air and argon. The thermal behavior of the zeolite/boric acid-based epoxy composites (total percentage 15 mass%) were compared with that of 15 mass% boric acid-based epoxy system and the neat epoxy resin. TG and DSC results revealed that the combination of 5 mass% zeolite and 10 mass% boric acid significantly increased the mid-point temperature and residue, and decreased the maximum decomposition rate of the epoxy composites at the heating.

Epoxy composites filled with boric acid and natural zeolite with different percentage (1, 5, and 10 wt%) were prepared. Hexamethylenediamine and polyethylenpolyamine were used as curing agents. The prepared samples and starting materials were examined using the methods of thermal analysis and scanning electron microscopy. The parameters of thermal decomposition in argon were analyzed. The limiting oxygen index was calculated in accordance with Van Krevelen and Hoftyzer equation. The thermal characteristics of the studied composites depend on the filler content. The results showed that the incorporation of 10 wt% fillers both boric acid and natural zeolite significantly improved the thermal properties of the obtained composites. Copyright © 2016 John Wiley & Sons, Ltd.

Natural fibres have recently become attractive to scientific community as an alternative reinforcement for fibre reinforced polymer (FRP) composites. As compared to conventional fibres, such as glass and carbon FRPs have low cost, fairly good mechanical properties, ecofriendly and bio-degradability characteristics. In the present work, bio based nanocomposites were successfully developed using cellulose nano whisker as filler in natural rubber latex by water evaporation method. The cellulose nano whisker were prepared from “Moringa oleifera” (Drum Stick vegetable Fibre) by acid hydrolysis. The morphology of cellulose whiskers/NR nanocomposites was investigated by Scanning Electron Microscope. The presence of nano cellulose whiskers (CW) in the NR matrix was observed by using Fourier transfer-infra red (FTIR) spectroscopy. The tensile properties such as tensile strength, tensile modules and elongation at break were measured by Universal Testing Machine. Thermal degradation of the nanocomposites were also analyzed using thermal gravimetric analysis (TGA). The result of the study shows that CW in the nanocomposites prepared during this study are randomly oriented and distributed homogeneously throughout the matrix. The FTIR analysis provided clear evidence of the presence of nano CW in the NR matrix that can be observed by the absorption peaks at 1033 and 1057 cm−1 assigned to C–O stretching of cellulose and TGA analysis showed the thermal stability of the nanocomposites increased with increasing CW, tensile strength and modulus values were also increased with CW addition. Hence the present study shows that the cellulose nano whiskers from Moringa oleifera has improved the properties of natural rubber based composite and can be considered as a good natural reinforcing material for future applications.

This chapter gives an introduction on the general aspects of cellulose, natural rubber and their bionanocomposites. A brief literature review on what has been done so far on the cellulose, natural rubber nanocomposites research area is also included in this chapter. This chapter also describes the structure, properties and characterization of cellulose as a biobased nanomaterial in natural rubber.

The present chapter deals with a brief account on various topics in rubber based bionanocomposites: preparation and state of art. This chapter discussed with different topics such as cellulose based rubber nanocomposites, chitin based rubber nanocomposites, applications of chitin based rubber nanocomposites, chitin in rubber based blends and micro composites, starch in rubber based blends and micro composites, polylactic acid based rubber composites and nanocomposites, applications of rubber based biocomposites and bionanocomposites, vinyl ester (BisGMA)/SEBS/f-MWCNTs based nanocomposites preparation and applications and starch based rubber nanocomposites.

The present chapter deals with a brief account on various topics in rubber nano blends preparation, characterization and applications. This chapter discussed with different topics such natural rubber nano blends, nitrile rubber latex blends, polyurethane rubber based nano blends, chlorosulphonated rubber based nano blends, polybutadiene rubber based nano blends, styrene butadiene rubber based nano blends, polychloroprene rubber based nano blends and ethylene propylene diene rubber nano blends.

Novel green flame retardant systems based on a complex of cyclodextrin nanosponges and phosphorus derivatives (namely, triethylphosphate and ammonium polyphosphate) have been prepared. The above additives have been subsequently melt compounded with polypropylene, linear low density polyethylene or polyamide 6 in order to improve the thermal stability of the latter polymers and their flame retardancy properties (assessed by combustion and flammability tests). The role of cyclodextrin nanosponges both as a carbon source and a foaming agent in such intumescent formulations has been demonstrated: indeed, the phosphorus derivatives are embedded and protected by the nanosponge architectures and thus are able to generate phosphoric acid directly in situ at high temperatures. As a consequence, cyclodextrin nanosponges dehydrate in presence of this acid source, giving rise to water vapour, favouring char formation and thus significantly enhancing the polymer resistance toward combustion.

Crosslinked natural rubber (NR) nanocomposites were prepared using cellulose nanowhiskers (CNWs) that were extracted from bamboo pulp residue of newspaper production, as the reinforcing phase. The coagulated NR latex containing bamboo nanowhiskers (master batch) was compounded with solid NR and vulcanizing agents using a two-roll mill and subsequently cured to introduce crosslinks in the NR phase. No evidence of micro-scaled aggregates of cellulose nanowhiskers in NR matrix was observed in Scanning Electron Microscopy (SEM) images. The addition of CNWs had a positive impact on the tensile strength, E-modulus, storage modulus, tan delta peak position and thermal stability of the crosslinked NR. Theoretical modeling of the mechanical properties showed a lower performance than predicated and therefore further process optimization and/or compatibilization are required to reach the maximum potential of these nanocomposites.

The addition of small amounts (up to 9 wt%) of chitin microsized particles, originating from shellfish waste, to carboxylated styrene-butadiene rubber (XSBR) matrix (as received and annealed to 100°C) has been studied. In particular, this study concentrated on their mechanical (creep investigation by nanoindentation and dynamical-mechanical analysis), thermal (differential scanning calorimetry and thermogravimetry) and swelling behaviour (toluene absorption) and was completed by morphological characterisation by scanning electron microscopy and atomic force microscopy. The results show that annealing has a limited effect on materials properties, effects which are further reduced by the addi- tion of growing amounts of crab chitin. It should be noted that the limited filler content used in the study does not substan- tially modify the linear creep behaviour of XSBR for sufficiently long loading times. The thermal stability of the system does also appear to be preserved even with the maximum chitin content added, while it serves sufficiently as an effective barrier against aromatic solvent absorption.

Received 9 May 2011; accepted 28 June 2011DOI 10.1002/app.35176Published online in Wiley Online Library (wileyonlinelibrary.com).ABSTRACT: This article investigates the transport behav-ior of three aromatic organic solvents, viz. benzene, toluene,and p-xylene in natural rubber nanocomposite membranescontaining cellulose nanofibres (CNFs) and cellulose nano-whiskers (CNWs) isolated from bamboo pulp. The solventmolecules act as molecular probes to study the diffusion,sorption, and permeation through the nanocomposites, andprovide information on the nanocomposite structure and ma-trix–filler interactions. Both the nanocelluloses were found todecrease the uptake of aromatic solvents in nanocompositemembranes, but the effect was more significant in the caseon nanofibers compared to nanowhiskers. Furthermore, theuptake decreased with increased penetrant size; being thehighest for benzene and the lowest for p-xylene. Transportparameters such as diffusion coefficient, sorption coefficient,and permeation coefficient have been calculated. Comparisonof the experimental values of equilibrium solvent uptakewith the predicted values indicated that both the nanocellu-loses have restricted the molecular mobility at the interphaseand thereby decreased the transport of solvents through thematerials; being more significant for nanofibers. The resultsshowed that both the used cellulosic nanomaterials act asfunctional additives capable of manipulating and tailoringthe transport of organic solvents through elastomeric mem-branes, even at concentrations as low as 2.5 wt %.

Nature is gifted with several nanomaterials which could be easily prepared from animals and plants. Cellulose, chitin and starch are abundant, natural, renewable and biodegradable polymers. By intelligent processing techniques they could be used as classical nano reinforcing elements in polymers. They are often called whiskers. These whiskers are almost defect free and as a result, their properties are comparable to perfect crystals. In most cases, aqueous suspensions of these nano crystallites are prepared by acid hydrolysis process. The object of this treatment is to dissolve away regions of low lateral order so that the water-insoluble, highly crystalline residue may be converted into a stable suspension by subsequent vigorous mechanical shearing action. The reinforcing ability of these natural whiskers stem from their chemical nature and hierarchical structure. During the past decade, many studies have been devoted to mimic biocomposites by blending natural whiskers from waste and biomass sources with various polymer matrices. In this review article, the recent advances on the preparation and characterization of nanowhiskers from waste and biomass and their polymer nanocomposites have been reported. Finally the emerging applications are also discussed.

The polymeric materials are characterized by high flammability. The use of flame retardants in order to reduce the flammability of polymers can lead to the formation of toxic gaseous products under fire conditions. In this work we studied the effect of boric acid on the volatile products of thermooxidative degradation of epoxy polymers. The comparative investigations were carried out on the samples of the unfilled epoxy resin and epoxy resin filled with a boric acid at percentage 10 wt. %. The analysis of the volatile decomposition products and thermal stability of the samples under heating in an oxidizing medium was performed using a thermal mass-spectrometric analysis. It is found that the incorporation of boric acid into the polymer matrix increases the thermal stability of epoxy composites and leads to a reduction in the 2-2.7 times of toxic gaseous products.

The epoxy polymers are characterized by low thermal stability and high flammability. Nanoparticles are considered to be effective fillers of polymer composites for improving their thermal and functional properties. In this work, the epoxy composites were prepared using epoxy resin ED-20, polyethylene polyamine as a hardener, aluminum nanopowder and boric acid fine powder as flame-retardant filler. The thermal characteristics of the obtained samples were studied using thermogravimetric analysis and differential scanning calorimetry. The mechanical characteristics of epoxy composites were also studied. It was found that an addition of all fillers enhances the thermal stability and mechanical characteristics of the epoxy composites. The best thermal stability showed the epoxy composite filled with boric acid. The highest flexural properties showed the epoxy composite based on the combination of boric acid and aluminum nanopowder.

The present chapter deals with a brief account on various topics in polyaniline-based blends, composites, and nanocomposites. This chapter discussed with different topics such as polyaniline structure–properties relationship; modification of polyaniline; polyaniline nano-/micromaterials–based blends and composites; polyaniline-based thermoplastic blends; polyaniline-based blends: natural rubber and synthetic rubber; polyaniline-based composites and nanocomposites; characterization of polyaniline-based blends, composites, and nanocomposites; polyaniline/natural polymer composites and nanocomposites; applications of polyaniline-based blends, composites, and nanocomposites; other applications of polyaniline-based blends, composites, and nanocomposites; and polyaniline–nanomaterial composites: structural, optical, and electrical properties.

The thermal properties of epoxy composites filled with boric acid fine powder at different percentage were studied. Epoxy composites were prepared using epoxy resin ED-20, boric acid as flame-retardant filler, hexamethylenediamine as a curing agent. The prepared samples and starting materials were examined using methods of thermal analysis, scanning electron microscopy and infrared spectroscopy. It was found that the incorporation of boric acid fine powder enhances the thermal stability of epoxy composites.

Polyoxymethylene (POM) is a semicrystalline polymeric material belonging to engineering thermoplastics because of its low friction and wear characteristics and its excellent balance of mechanical properties and chemical resistance to most solvents, chemicals and fuels at room temperature. Hence, such polymers are used to serve as an alternative to metals. As formaldehyde was initially the raw material used in the manufacturing of commercial POM it is also referred to as polyformal or polyacetal. Among the polymers obtained from the polymerization of aldehydes, POM is the only one that could reach commercial signifi cance. Polyoxymethylene resins have traditionally covered homopolymers (POM-H) and copolymers (POM-C), and more recently terand block-copolymers have been developed. Today, most of the POM resins manufactured worldwide are used in the production of automotive parts followed by electrical and electronic parts, and industrial parts. Hence, at present most of the POM is manufactured and consumed in Asia. However, besides Asia, manufacturing sites with high production capacities are also located in Germany and the USA.

Elastomers are becoming an inevitable part of day to day life. The materials based on elastomers have tremendous applications in almost all areas of life. The present chapter deals with a brief account on various types of elastomers, elastomeric based blends and IPNs (interpenetrating networks). Various classes of elastomers, and blends are addressed by giving importance to the interfacial compatibility of different phases. Topics such as immiscible rubber blends, rubber/thermoplastic blends (micro and nano structured), rubber-thermoset blends (micro and nano structured), interphase modification and compatibilization, interpenetrating polymer networks, micro and nanofillers in rubbers have been very briefly discussed. Finally the applications, new challenges and opportunities of these elastomeric based blends and IPNs are also discussed.

The present chapter deals with a brief account on various types of natural polymers such as cellulose, chitin, starch, soy protein, casein, hemicelluloses, alginates, polylactic acid and polyhydroxyalkanoates etc. Blends, composites and nanocomposites based on these polymers have been very briefly discussed. Finally the applications, new challenges and opportunities of these biomaterials are also discussed.

Green composites constitute a loosely defined family of materials which are obtained from renewable resources and are degradable through action of living organisms. These materials offer a possible alternative to traditional non-biodegradable materials where recycling is unpractical or not economical. Renewable sources of polymeric materials offer an answer to maintaining sustainable development of economically and ecologically attractive technology. When a biodegradable material (neat polymer, blended product, or composite) is obtained completely from renewable resources we may call it a green polymeric material. Nature provides an impressive array of polymers which are generally biodegradable, and which have the potential to replace many current polymers as biodegradation is part of the natural biogeochemical cycle. Natural polymers, such as proteins, starch, chitin and cellulose are examples of such polymers. In addition, Natural rubber latex (NR) Poly lactic acid (PLA) from corn and polyalkanoates (PHA) from bacteria are other green polymers.Green nanomaterials or bio nanomaterials could be easily prepared from animals and plants. These nano sized materials’ properties are comparable to perfect crystals. In most cases, aqueous suspensions of these nano crystallites are prepared by simple mechanical stirring and acid hydrolysis process. The object of this treatment is to dissolve away regions of low lateral order so that the water-insoluble, highly crystalline residue may be converted into a stable suspension by subsequent vigorous mechanical shearing action. During the past decade, many studies have been devoted to mimic biocomposites by blending natural bionanomaterials with various polymer matrices. In this chapter, the recent advances on the preparation and characterization of different type of green nano materials and their polymer nanocomposites are discussed and reported. Macro micro and nanocomposites based on fully renewable polymers (which can be called fully green composites) and their applications are discussed in detail.

The chapter presents a brief account of various topics in starch-based blends, composites and nanocomposites, including structure–property relationships, preparation and characterization of starch nanocrystals, natural fibre-reinforced thermoplastic starch composites, applications of starch nanocrystal-based blends, composites and nanocomposites, chemically modified thermoplastic starches, outstanding features of starch-based hydrogel nanocomposites, fracture and failure of starch-based composites, application of starch-based nanocomposites in the food industry and effects of additives on the properties of starch.

Validerad; 2012; Bibliografisk uppgift: Nanocomposites were prepared using two bioresources, viz., cellulose nanofibers (CNFs) extracted from bamboo paper-pulp waste as the reinforcing phase and natural rubber (NR) as the matrix phase. CNFs with diameters up to 50 nm were isolated from bamboo pulp waste, and nanocomposites with 5 and 10% CNFs were obtained via two-roll mill mixing of solid natural rubber with a master batch containing 20 wt% CNFs. The NR phase was cross-linked using sulphur vulcanization. The morphology studies showed that the dispersion of CNF in NR matrix was not optimal, and some aggregates were visible on the fracture surface. The tensile strength and modulus at 50% elongation increased for the nanocomposites with the addition of CNFs, accompanied by a moderate decrease in elongation at break. The storage modulus of the natural rubber significantly increased above its glass-rubber transition temperature upon nanofiber addition. The addition of CNFs also had a synergistic impact on the thermal stability of natural rubber. The susceptibility to organic solvents decreased significantly for the nanocomposites compared to crosslinked NR, which indicated restriction of polymer chain mobility in the vicinity of the nanosized CNFs in the NR matrix.; 20120807 (ysko)